performance - Active Record Rails 中唯一性验证的效率

Question

在为rails中的列创建具有唯一值的记录时，哪个更有效 放置唯一性验证与查找记录是否存在具有相同值并基于存在创建。

在编码和性能方面哪个更有效。

Answer 1

A database uniqueness constraint will give you the highest performance.

At the application level, whether you are using validates_uniqueness_of or manually finding if the record exists, the performance will basically be the same. In fact, that is exactly how it is implemented in Rails: https://github.com/rails/rails/blob/0d73d6e7b6dd1900f105397460b777ef6c03d3b6/activerecord/lib/active_record/validations/uniqueness.rb#L33